Process for the manufacture of enzyme and perborate-containing detergent compositions

ABSTRACT

Production of enzyme and perborate-containing detergent compositions by spraying liquid or pasty detergent components onto solid, powdery detergent components with the resultant formation of a readily flowable granulate. Solid detergent components comprising a powder mixture consisting substantially of one or more alkali metal salts as a builder substance and sodium perborate are fluidized by means of air and the fluidized powder mixture is granulated by spraying liquid detergent components comprising water or an aqueous solution or suspension of one or more binders and optionally a surface-active substance, onto it. The enzyme may be present in the powder mixture or in the water or aqueous solution or suspension to be sprayed thereonto.

United States Patent Grimm et al.

[ 51 July 11, 1972' [22] Filed: Jan. 26, 1970 [21] Appl.No.: 5,945

[30] Foreign Application Priority Data Feb. 11, 1969 Germany ..P 19 06 705.1 Jan. 2, 1970 Germany ..P 20 08 069.5

[52] US. Cl ..252/99, 195/63, 252/89, 252/D1G. 12, 252/137, 252/138, 474/94 [51] Int. Cl. ..C1ld 7/56 [58] Field of Search ..252/99, 89, DIG. 12, 135, 137,

[56] References Cited UNITED STATES PATENTS 3,538,004 3/1970 Gabler et al. ..252/99 3,519,570 7/1970 McCarty ...252/99 x 3,451,935 6/1969 Roald et al ..252/89 x Primary Examiner-Mayer Weinblatt Attorney-Connolly and Hutz [57] ABSTRACT Production of enzyme and perborate-containing detergent compositions by spraying liquid or pasty detergent components onto solid, powdery detergent components with the resultant formation of a readily flowable granulate. Solid detergent components comprising a powder mixture consisting substantially of one or more alkali metal salts as a builder substance and sodium perborate are fluidized by means of air and the fluidized powder mixture is granulated by spraying liquid detergent components comprising water or an aqueous solution or suspension of one or more binders and optionally a surface-active substance, onto it. The enzyme may be present in the powder mixture or in the water or aqueous solution or suspension to be sprayed thereonto.

8 Claims, No Drawings PROCESS FOR THE MANUFACTURE OF ENZYME AND PERBORATE-CONTG DETERGENT COMPOSITIONS The present invention relates to a process for the manufacture of detergent compositions containing enzymes and perborates, which comprises spraying liquid or pasty detergent components onto solid, powdery and air-fluidized detergent components with the resultant formation of a granulated detergent composition having good flow properties.

It is known that conventional detergents can be used in combination with pulverulent enzymes, to improve their cleansing effects. To this end, it is merely necessary, for example, to mechanically dry blend the pulverulent enzyme with the further detergent components, which are most frequently used in the form of readily flowable granules. In view of the different particle size and density of the blend components, the blends so made rapidly tend to disintegrate into their components. Detergent formulations so made, therefore, are not capable of being stored. In addition thereto, the fine-powdered enzyme present in detergents so formulated may irritate the skin of persons handling them, or produce further disadvantageous physiological phenomena. It has also been found that the enzymes present in dry-blend powder having the composition indicated above may soon lose their initial activity.

In an attempt to avoid the disadvantageous phenomena encountered in the production of enzyme-containing detergents, for example, by mechanical dry blending of the blend components, it has been suggested in South African Pat. No. 67/2442 that the fine-powdered enzyme be granulated by means of water and adhered to a carrier of good flowability, suitable for use as a detergent component. The water can, for example, be sprayed onto the solid detergent components. The carriers suggested to be used include anhydrous or partially hydrated sodium tripolyphosphate, or a granulate made therefrom together with, for example, sodium carboxymethylcellulose, corrosion inhibitors, optical brighteners or perfumes. The water used for adhering the enzyme to the carrier is employed in a quantity sufficient to simultaneously hydrate at most 90 percent of the carrier. The granulated matter so made has been found to have a satisfactory flowability.

South African Pat. No. 67/2415 describes a process for the manufacture of free-flowing, enzyme-containing granulated detergents, wherein the surface of the granulated base detergent, for example sodium tripolyphosphate or sodium perborate, is first rendered glutinous by blending it with a low melting, non-ionic surface-active material, and the granulated particles are then powdered or dusted with fine-powdered enzyme. A preferred feature of this process comprises using a blend of base detergent and enzyme powder, spraying the surface-active substance, which is liquefied by heating it, onto the blend with thorough agitation, and thereby adhering the enzyme to the base detergent. The useful enzymes include hydrolases, such as proteases, esterases, carbohydrases or nucleases, and the useful surface-active substances include, for example, polyethylene glycol or polyoxymethylene glyceride esters. This dusting process produces granulated matter having a considerable proportion of small granulate particles therein. This is undesirable in the production of detergents as the flowability of the detergent is reduced thereby.

A further process for the manufacture of a biologically active and perborate containing detergent has been reported in South-African Pat. No. 67/2413 which comprises first spraydrying sodium tripolyphosphate and enzyme so as to obtain a granulate and then dry-blending the granulate with sodium perborate, a granulate composition of further detergent components, such as sodium silicate, carboxymethylcellulose and a surface-active substance.

Inasmuch as these conventional biologically-active, i.e. enzyme-containing detergent formulations contain a perborate, it is necessary for all of the processes used for making them to be carried out so as to avoid the formation of a homogeneous, sodium perborate and enzyme-containing granulate, bearing in mind that the granulating step simultaneously effects hydration of the base detergent, for example sodium tripolyphosphate, with the resultant formation of the corresponding hexahydrate. The production of granulates having the enzyme incorporated in the individual granulate particles is, however, highly desirable for physiological reasons and for reasons of homogeneity and stability to storage, and is further desirable in those cases in which the granulates are found to combine these properties with good flowability. These are requirements which the products produced by the processes reported in South-African Pat. Nos. 67/2415 and 67/2413 fail to meet. The poor compatibility of enzymes with sodium perborate and the preconception that they would soon lose their initial activity during granulation with water coupled with hydration of the base detergent have long been held to forbid the use of the process described in South-African Pat. No. 67/2442 for the production of a biologically active detergent having satisfactory flow properties, with the incorporation of perborate and formation of a homogeneous granulate in a single step.

In clear contrast with this preconception, the present invention now provides a single step process for the manufacture of granulated, biologically -active and perborate-containing detergent compositions which combine free flow properties with freedom from dust and further combine a uniform particle size with a constant apparent density.

The process of the present invention for the manufacture of enzyme and perborate-containing detergent compositions by spraying liquid or pasty detergent components onto solid, powdery detergent components with the resultant formation of a readily flowable granulate comprises more particularly air-fluidizing the solid detergent components comprising a powder mixture consisting substantially of one or more alkali metal salts as a builder substance and sodium perborate, the cation of the alkali metal salt being a lithium, sodium, potassium or ammonium ion, and the acid salt component being sulfuric acid, silicic acid, disilicic acid, carbonic acid, an oligo or polyphosphoric acid, nitrilotriacetic acid, ethylenediaminetetracetic acid, a homopolymer or copolymer of an unsaturated aliphatic polycarboxylic acid, a copolymer of an unsaturated aliphatic polycarboxylic acid with an alkylene, an unsaturated monocarboxylic acid or a further vinyl compound, a copolymer of a vinylphosphonic acid with acrylic acid or a further vinyl compound, a polyvinylphosphonic acid, an aminopolycarboxylic acid, a hydroxyalkylaminopolycarboxylic acid, phytic acid, an alkylenephosphonic acid, a hydroxyalkylenephosphonic acid or an aminoalkylenephosphonic acid; and effecting granulation of the fluidized powder mixture by spraying the liquid detergent components comprising water or an aqueous solution or suspension of one or more binders, such as cellulose ether, polyvinyl pyrrolidone, dextrin, alginates, agar-agar, gum arabic, tragacanth, polyvinyl alcohol, bassorin or guar gum and optionally a surface-active substance, onto it, whereby the enzyme may be in the powder mixture or in the water or aqueous solution or suspension to be sprayed thereonto.

In accordance with a preferred feature of the present process the builder substance is sodium tripolyphosphate with a phase-l-content of between 20 and 100, preferably 40 and 80, weight percent, or sodium pyrophosphate, sodium hexametaphosphate, trisodium nitrilotriacetate or tetrasodium ethylenediaminetetracetate. A further preferred feature comprises using sodium tripolyphosphate having an apparent density of more than 550 grams/liter, preferably between about 600 and 700 grams/liter.

Biologic activity can be imparted to the detergent composition of the present invention by means of a wide variety of enzymes, such as hydrolases, oxidoreductases, transferases, desmolases or isomerases, bacterial proteases being preferred.

in those cases in which a surface-active substance or a mixture of such substances, which may be anion-active or cationactive, ampholytic or non-ionic, is added to the detergent formulation, it is possible for it if liquid to be sprayed separately or in the form of an aqueous solution or suspension onto the solid, fluidized detergent components.

Apart from the essential solid detergent components specified hereinabove, the detergent composition of the present invention may contain further solid addends, for example perfumes, optical brighteners, desinfectants and peroxide stabilizers or activators, such as alkaline earth metal silicates, heavy metal salts or tetracetylethylene diamine.

Tylose is preferably used as the cellulose ether. The granulating step should conveniently be carried out with the use of a quantity of water sufficient to effect granulation of the builder. Between about 2 and 50 weight percent water, based on the builder, should conveniently be used to efiect hydration. In those cases in which the builder is sodium tripolyphosphate having a phase-I-content of between 20 and 100 weight percent, where the water is found to effect transformation into the hexahydrate, it is advantageous to use the water at a rate of between about 2 and 30 weight percent, based on the sodium tripolyphosphate.

The detergent composition should conveniently contain between 20 and 50 weight percent builder, between about 50 and weight percent sodium perborate and between about 0.2 and 2 weight percent enzyme. A turbulent air mixer, such as that described in British Pat. No. 1,118,908, should conveniently be used for effecting granulation of these components in those cases in which water is the granulating agent, which may be used in combination with further detergent addends, if desired. For the granulated detergent composition of the present invention it is accordingly possible to be made by the process reported in the above patent, wherein the solid detergent components, which may be premixed, if desired, are fluidized using a stream of air and the liquid detergent components are simultaneously sprayed through nozzles onto the fluidized blend. The air is passed through the turbulent air mixer at a rate and/or temperature sufficient to permit firstly the dissipation of the heat of hydration set free and secondly the maintenance of the temperature which is necessary for the hydration to take a fairly rapid course.

The detergent composition produced in accordance with the present invention is a homogeneous granulate composed of homogeneous individual particles that substantially contain the following components:

a. builder substances, namely alkali metal salts of which the cation is a lithium, sodium, potassium or ammonium ion and the acid salt component is sulfuric acid, silicic acid, disilicic acid, carbonic acid, an oligo or polyphosphoric acid, nitrilotriacetic acid, ethylenediaminetetracetic acid, a homopolymer or copolymer of an unsaturated aliphatic polycarboxylic acid, a copolymer of an unsaturated aliphatic polycarboxylic acid with an alkylene, an unsaturated monocarboxylic acid or further vinyl compound, a copolymer of a vinylphosphonic acid with acrylic acid or a further vinyl compound, a polyvinylphosphonic acid, an aminopolycarboxylic acid, a hydroxyalkylaminopolycarboxylic acid, phytic acid, an alkylenephosphonic acid, a hdyroxyalkylenephosphonic acid or an aminoalkylenephosphonic acid;

b. sodium perborate monohydrate or tetrahydrate;

c. one or more enzymes;

d, binders, such as polyvinyl pyrrolidone, cellulose ether, dextrin, alginates, agar-agar, gum arabic, tragacanth, polyvinyl alcohol, bassorin or guar gum, and optionally e. one or more surface-active substances, perfumes, optical brighteners, desinfectants and peroxide stabilizers or activators, such as alkaline earth metal silicates, heavy metal salts or tetracetylethylene diamine.

The builder substances defined under item a) hereinabove comprise more particularly alkali metal salts of which the acid component may be one of the following compounds:

Polymaleic acid and its copolymers with itaconic acid or ethylene, styrene, acrylic acid or polyvinyl alcohol; polyvinylphosphonic acid and its copolymer with acrylic acid, nitrilotriacetic acid, ethylenediaminetetracetic acid, diethylenetriaminepentacetic acid, dihydroxyethylene glycine, N-( Z-hydroxyethyl)-ethylenediaminediacetic acid, N- (Z-hydroxyethyl )-nitriloacetic acid, dior trimethylenephosphonic acid, hydroxyethane, hydroxypropane, hydroxybutane-l,l-diphosphonic acid, hydroxyethanetriphosphonic acid, amino-bis-(l-ethylphosphonic acid), ethylenediaminetetra-( l-ethylphosphonic acid), ethylenediamine-tetra (methylphosphonic acid) or diethylenetriarninepentamethylphosphonic acid.

The quality of the individual particles forming the granulated detergent composition of the present invention can be improved by dissolving or suspending one of the binders specified above in the spray water.

As compared with conventional detergent formulations of analogous qualitative composition, the granulated detergent composition made by the process of the present invention has the distinction of perfectly satisfying the requirements which a modern detergent has to meet, such as good flowability, uniform particle size, constant apparent density and freedom from dust. In addition thereto, the perborate has unexpectedly been found not to affect the activity of the enzyme during granulation, and that the perborate remains undecomposed. A further advantage resides in the fact that merely one step is necessary for the production of the detergent composition of the present invention.

EXAMPLE 1 A blend of 200 kg sodium tripolyphosphate with a phase-l-content of more than 50 percent and an apparent density of 580 grams/liter,

20 kg lightweight sodium silicate (Sikalon),

20 kg magnesium silicate,

20 kd carboxymethylcellulose (Tylose Cp 1500),

kg sodium perborate,

50 kg lightweight sodium sulfate and 1 kg optical brightener was introduced into a turbulent air mixer and fluidized therein, by means of a stream of air. 50 kg liquid surface-active substance (Genapol 0-120) and 40 kg water having 3.6 kg of a blend of highly active bacterial proteases dissolved therein were sprayed onto the fluidized blend, through separate sets of nozzles arranged in annular fashion. The temperature prevailing in the turbulent air mixer was about 25C. A readily flowable granulated detergent composition was obtained. It had an apparent density of 410 grams/liter and a proteolytic activity of 1,300 Loehlein-Vollhard units, per gram granulated detergent. The sodium perborate could not be found to have been decomposed.

EXAMPLE 2 The blend described in Example 1 was prepared and fluidized together with 3.6 kg highly active bacterial protease, in a turbulent air mixer. 40 kg water and 50 kg liquid surfaceactive substance were sprayed onto the fluidized blend, through separate sets of nozzles arranged in annular fashion. The resulting granulate had a proteolytic activity of 1,300 Loehlein-Vollhard units, per gram granulated detergent. The granulate had a good flowability. The perborate remained unchanged.

EXAMPLE 3 (Comparative Example) The blend of Example 1 was prepared and fluidized in a turbulent air mixer, by means of a stream of air. 50 kg surface active substance (Genapol O-l 20) and 40 kg water were sprayed onto the fluidized blend, through separate sets of nozzles arranged in annular fashion. The resulting granulated detergent composition was mechanically blended with 3.6 kg of the highly active protease used in Example 1. The finished detergent composition was found to have a proteolytic activity of about 1,300 Leohlein-Vollhard units.

EXAMPLE 4 A blend of 290 kg sodium tripolyphosphate with a phase-I-content of more than 50 percent and an apparent density of 590 grams/liter,

30 kg trisodium nitrilotriacetate,

5 kg tetrasodium ethylenediaminetetracetate,

70 kg lightweight sodium silicate (Sikalon),

20 kg dextrin,

250 kg sodium perborate tetrahydrate,

90 kg lightweight sodium sulfate,

10 kg powdered soap and 1 kg optical brightener was introduced into a turbulent air mixer and fluidized therein, by means of a stream of air. 90 kg liquid surface-active substance (Genapol -120) and 140 kg water having 2.0 kg highly active bacterial protease dissolved therein were sprayed'onto the fluidized blend, through separate sets of nozzles arranged in annular fashion. The temperature prevailing in the turbulent air mixture was about 23C. A readily flowable granulated detergent composition was obtained. It had an apparent density of 430 grams/liter and a proteolytic activity of 400 Lohlein-Vollhard units, per gram granulated detergent.

EXAMPLE 5 A blend of 160 kg sodium tripolyphosphate with a phase-l-content of more than 50 percent and an apparent density of 590 grams/liter,

160 kg trisodium nitrilotriacetate,

5 kg tetrasodium-ethylenediaminetetracetate,

70 kg lightweight sodium silicate (Sikalon),

20 kg dextrin,

250 kg sodium perborate tetrahydrate,

90 kg lightweight sodium sulfate,

kg powdered soap and 1 kg optical brightener was introduced into a turbulent air mixer and fluidized therein, by means of a stream of air. 90 kg liquid surface active substance (Genapol O-l20) and 120 kg water having 2.0 kg highly active bacterial protease dissolved therein were sprayed onto the fluidized blend, through separate sets of nozzles arranged in annular fashion. The temperature prevailing in the turbulent air mixer was about 22C. A readily flowable granulated detergent composition was obtained. It had an apparent density of 420 grams/liter and a proteolytic activity of 400 Lohlein-Vollhard units, per gram granulated detergent.

We claim:

1. In the process for the manufacture of granular detergent compositions essentially containing an enzyme selected from the group consisting of hydrolases, oxidoreductases, transferases, desmolases and isomerases, an alkali perborate and a builder salt, the cation of the builder salt being a lithium, sodium, potassium or ammonium ion, and the acid salt component having at least one member selected from the group consisting of sulfuric acid, silicic acid, carbonic acid, pyrophosphoric acid, metaphosphon'c acid, tripolyphosphoric acid, nitrilotriacetic acid, and ethylenediaminetetracetic acid, by granulating the components of the detergent composition, the improvement which comprises air-fluidizing a powder mixture of the alkali perborate, the builder salt and the enzyme and effecting granulation by spraying an aqueous solution or suspension of at least one binder selected from the group consisting of carboxymethylcellulose, dextrin, agar-agar, gum arabic, tragacanth, bassorin and guar gum, onto the powder mixture.

2. The process as claimed in claim 1, wherein the builder substance is at least one member selected from the group consisting of sodium tripolyphosphate with a phase-l-content of between 20 and 100 weight percent, sodium pyrophosphate, sodium hexametaphosphate, trisodium nitrilotriacetate and tetrasodium ethylenediaminetetracetate.

3. The process as claimed in claim 1, wherein the builder substances are hydrated using a quantity of water, between about 2 and 5 0 weight percent, based on the builder substance.

4. The process as claimed in claim 1, wherein the detergent composition contains between about 20 and 50 weight percent builder, between about 50 and 10 weight percent sodium perborate and between about 0.2 and 2 weight percent enzyme.

5. The process as claimed in claim 1, wherein the granulated detergent composition is prepared in a turbulent air mixer provided with spray systems.

6. The process as claimed in claim 2, wherein the builder substance is sodium tripolyphosphate with a phase-l-content of between 40 and weight percent.

7. The process as claimed in claim 2, wherein the sodium tripolyphosphate has an apparent density of preferably between 600 and 700 grams/liter.

8. In the process for the manufacture of granular detergent compositions essentially containing an enzyme selected from the group consisting of hydrolases, oxidoreductases, transferases, desmolases and isomerases, an alkali perborate and a builder salt, the cation of the builder salt being a lithium, sodium, potassium or ammonium ion, and the acid salt component having at least one member selected from the group consisting of sulfuric acid, silicic acid, carbonic acid, pyrophosphoric acid, metaphosphoric acid, tripolyphosphoric acid, nitrilotn'acetic acid, and ethylenediaminetetracetic acid, by granulating the components of the detergent composition, the improvement which comprises air-fluidizing a powder mixture of the alkali perborate and the builder salt and effecting granulation by spraying an aqueous solution or suspension of the enzyme and of at least one binder selected from the group consisting of carboxymethylcellulose, dextrin, agar-agar, gum arabic, tragacanth, bassorin and a guar gun onto the powder mixture. 

2. The process as claimed in claim 1, wherein the builder substance is at least one member selected from the group consisting of sodium tripolyphosphate with a phase-I-content of between 20 and 100 weight percent, sodium pyrophosphate, sodium hexametaphosphate, trisodium nitrilotriacetate and tetrasodium ethylenediaminetetracetate.
 3. The process as claimed in claim 1, wherein the builder substances are hydrated using a quantity of water, between about 2 and 50 weight percent, based on the builder substance.
 4. The process as claimed in claim 1, wherein the detergent composition contains between about 20 and 50 weight percent builder, between about 50 and 10 weight percent sodium perborate and between about 0.2 and 2 weight percent enzyme.
 5. The process as claimed in claim 1, wherein the granulated detergent composition is prepared in a turbulent air mixer provided with spray systems.
 6. The process as claimed in claim 2, wherein the builder substance is sodium tripolyphosphate with a phase-I-content of between 40 and 80 weight percent.
 7. The process as claimed in claim 2, wherein the sodium tripolyphosphate has an apparent density of preferably between 600 and 700 grams/liter.
 8. In the process for the manufacture of granular detergent compositions essentially containing an enzyme selected from the group consisting of hydrolases, oxidoreductases, transferases, desmolases and isomerases, an alkali perborate and a builder salt, the cation of the builder salt being a lithium, sodium, potassium or ammonium ion, and the acid salt component having at least one member selected from the group consisting of sulfuric acid, silicic acid, carbonic acid, pyrophosphoric acid, metaphosphoric acid, tripolyphosphoric acid, nitrilotriacetic acid, and ethylenediaminetetracetic acid, by granulating the components of the detergent composition, the improvement which comprises air-fluidizing a powder mixture of the alkali perborate and the builder salt and effecting granulation by spraying an aqueous solution or suspension of the enzyme and of at least one binder selected from the group consisting of carboxymethylcellulose, dextrin, agar-agar, gum arabic, tragacanth, bassorin and a guar gum onto the powder mixture. 